Joint and Individual Mitochondrial DNA Variation and Cognitive Outcomes in Black and White Older Adults.

BACKGROUND: Mitochondrial dysfunction manifests in neurodegenerative diseases and other age-associated disorders. In this study, we examined variation in inherited mitochondrial DNA (mtDNA) sequences in Black and White participants from 2 large aging studies to identify variants related to cognitive function. METHODS: Participants included self-reported Black and White adults aged ≥70 years in the Lifestyle Interventions and Independence for Elders (LIFE; N = 1 319) and Health Aging and Body Composition (Health ABC; N = 788) studies. Cognitive function was measured by the Digit-Symbol Substitution Test (DSST), and the Modified Mini-Mental State Examination (3MSE) at baseline and over follow-up in LIFE (3.6 years) and Health ABC (10 years). We examined the joint effects of multiple variants across 16 functional mitochondrial regions with cognitive function using a sequence kernel association test. Based on these results, we prioritized meta-analysis of common variants in Black and White participants using mixed effects models. A Bonferroni-adjusted p value of <.05 was considered statistically significant. RESULTS: Joint variation in subunits ND1, ND2, and ND5 of Complex I, 12S RNA, and hypervariable region (HVR) were significantly associated with DSST and 3MSE at baseline. In meta-analyses among Black participants, variant m.4216T>C, ND1 was associated with a faster decline in 3MSE, and variant m.462C>T in the HVR was associated with a slower decline in DSST. Variant m.5460G>C, ND2 was associated with slower and m.182C>T in the HVR was associated with faster decline in 3MSE in White participants. CONCLUSIONS: Among Black and White adults, oxidative phosphorylation Complex I variants were associated with cognitive function.

Neighborhood factors and survival to old age: The Jackson Heart Study.

Few studies have evaluated environmental factors that predict survival to old age. Our study included 913 African American participants in the Jackson Heart Study (JHS) who resided in the tri-county area of the Jackson, MS metropolitan area and were 65-80 years at baseline. Participants were followed from 2000 through 2019 for the outcome of survival to 85 years old. We evaluated each of the following census tract-level measures of the social/physical environment as exposures: socioeconomic status, cohesion, violence, disorder, healthy food stores, residential land use, and walkability. We assessed mediation by physical activity and chronic conditions. As a complementary ecologic analysis, we used census-tract data to examine factors associated with a greater life expectancy. A total of 501 (55%) JHS participants survived to age 85 years or older. Higher social cohesion and greater residential land use were modestly associated with survival to old age (risk difference = 25%, 95% CI: 0-49%; and 4%, 95% CI: 1-7%, respectively). These neighborhood effects were modestly mediated through leisure time physical activity; additionally, social cohesion was mediated through home and yard activity. In our ecologic analysis, a greater percentage of homeowners and a greater proportion of people living in partnered families were associated with higher census-tract level life expectancy. African American older adults living in residential neighborhoods or neighborhoods with high social cohesion were more likely to survive to old age.

Regression discontinuity design to evaluate the effect of statins on myocardial infarction in electronic health records.

Regression discontinuity design (RDD) is a quasi-experimental method intended for causal inference in observational settings. While RDD is gaining popularity in clinical studies, there are limited real-world studies examining the performance on estimating known trial casual effects. The goal of this paper is to estimate the effect of statins on myocardial infarction (MI) using RDD and compare with propensity score matching and Cox regression. For the RDD, we leveraged a 2008 UK guideline that recommends statins if a patient's 10-year cardiovascular disease (CVD) risk score > 20%. We used UK electronic health record data from the Health Improvement Network on 49,242 patients aged 65 + in 2008-2011 (baseline) without a history of CVD and no statin use in the two years prior to the CVD risk score assessment. Both the regression discontinuity (n = 19,432) and the propensity score matched populations (n = 24,814) demonstrated good balance of confounders. Using RDD, the adjusted point estimate for statins on MI was in the protective direction and similar to the statin effect observed in clinical trials, although the confidence interval included the null (HR = 0.8, 95% CI 0.4, 1.4). Conversely, the adjusted estimates using propensity score matching and Cox regression remained in the harmful direction: HR = 2.42 (95% CI 1.96, 2.99) and 2.51 (2.12, 2.97). RDD appeared superior to other methods in replicating the known protective effect of statins with MI, although precision was poor. Our findings suggest that, when used appropriately, RDD can expand the scope of clinical investigations aimed at causal inference by leveraging treatment rules from everyday clinical practice.

Aging Hearts in a Hotter, More Turbulent World: The Impacts of Climate Change on the Cardiovascular Health of Older Adults.

PURPOSE OF REVIEW: Climate change has manifested itself in multiple environmental hazards to human health. Older adults and those living with cardiovascular diseases are particularly susceptible to poor outcomes due to unique social, economic, and physiologic vulnerabilities. This review aims to summarize those vulnerabilities and the resultant impacts of climate-mediated disasters on the heart health of the aging population. RECENT FINDINGS: Analyses incorporating a wide variety of environmental data sources have identified increases in cardiovascular risk factors, hospitalizations, and mortality from intensified air pollution, wildfires, heat waves, extreme weather events, rising sea levels, and pandemic disease. Older adults, especially those of low socioeconomic status or belonging to ethnic minority groups, bear a disproportionate health burden from these hazards. The worldwide trends responsible for global warming continue to worsen climate change-mediated natural disasters. As such, additional investigation will be necessary to develop personal and policy-level interventions to protect the cardiovascular wellbeing of our aging population.

Association Between Myocardial Strain and Frailty in CHS.

BACKGROUND: Myocardial strain, measured by speckle-tracking echocardiography, is a novel measure of subclinical cardiovascular disease and may reflect myocardial aging. We evaluated the association between myocardial strain and frailty-a clinical syndrome of lack of physiological reserve. METHODS: Frailty was defined in participants of the CHS (Cardiovascular Health Study) as having ≥3 of the following clinical criteria: weakness, slowness, weight loss, exhaustion, and inactivity. Using speckle-tracking echocardiography data, we examined the cross-sectional (n=3206) and longitudinal (n=1431) associations with frailty among participants who had at least 1 measure of myocardial strain, left ventricular longitudinal strain (LVLS), left ventricular early diastolic strain rate and left atrial reservoir strain, and no history of cardiovascular disease or heart failure at the time of echocardiography. RESULTS: In cross-sectional analyses, lower (worse) LVLS was associated with prevalent frailty; this association was robust to adjustment for left ventricular ejection fraction (adjusted odds ratio, 1.32 [95% CI, 1.07-1.61] per 1-SD lower strain; P=0.007) and left ventricular stroke volume (adjusted OR, 1.32 [95% CI, 1.08-1.61] per 1-SD lower strain; P=0.007). In longitudinal analyses, adjusted associations of LVLS and left ventricular early diastolic strain with incident frailty were 1.35 ([95% CI, 0.96-1.89] P=0.086) and 1.58 ([95% CI, 1.11-2.27] P=0.013, respectively). Participants who were frail and had the worst LVLS had a 2.2-fold increased risk of death (hazard ratio, 2.20 [95% CI, 1.81-2.66]; P<0.0001). CONCLUSIONS: In community-dwelling older adults without prevalent cardiovascular disease, worse LVLS by speckle-tracking echocardiography, reflective of subclinical myocardial dysfunction, was associated with frailty. Frailty and LVLS have an additive effect on mortality risk.

Association Between Income Inequality and County-Level COVID-19 Cases and Deaths in the US.

Importance: Socioeconomically marginalized communities have been disproportionately affected by the COVID-19 pandemic. Income inequality may be a risk factor for SARS-CoV-2 infection and death from COVID-19. Objective: To evaluate the association between county-level income inequality and COVID-19 cases and deaths from March 2020 through February 2021 in bimonthly time epochs. Design, Setting, and Participants: This ecological cohort study used longitudinal data on county-level COVID-19 cases and deaths from March 1, 2020, through February 28, 2021, in 3220 counties from all 50 states, Puerto Rico, and the District of Columbia. Main Outcomes and Measures: County-level daily COVID-19 case and death data from March 1, 2020, through February 28, 2021, were extracted from the COVID-19 Data Repository by the Center for Systems Science and Engineering at Johns Hopkins University in Baltimore, Maryland. Exposure: The Gini coefficient, a measure of unequal income distribution (presented as a value between 0 and 1, where 0 represents a perfectly equal geographical region where all income is equally shared and 1 represents a perfectly unequal society where all income is earned by 1 individual), and other county-level data were obtained primarily from the 2014 to 2018 American Community Survey 5-year estimates. Covariates included median proportions of poverty, age, race/ethnicity, crowding given by occupancy per room, urbanicity and rurality, educational level, number of physicians per 100 000 individuals, state, and mask use at the county level. Results: As of February 28, 2021, on average, each county recorded a median of 8891 cases of COVID-19 per 100 000 individuals (interquartile range, 6935-10 666 cases per 100 000 individuals) and 156 deaths per 100 000 individuals (interquartile range, 94-228 deaths per 100 000 individuals). The median county-level Gini coefficient was 0.44 (interquartile range, 0.42-0.47). There was a positive correlation between Gini coefficients and county-level COVID-19 cases (Spearman ρ = 0.052; P < .001) and deaths (Spearman ρ = 0.134; P < .001) during the study period. This association varied over time; each 0.05-unit increase in Gini coefficient was associated with an adjusted relative risk of COVID-19 deaths: 1.25 (95% CI, 1.17-1.33) in March and April 2020, 1.20 (95% CI, 1.13-1.28) in May and June 2020, 1.46 (95% CI, 1.37-1.55) in July and August 2020, 1.04 (95% CI, 0.98-1.10) in September and October 2020, 0.76 (95% CI, 0.72-0.81) in November and December 2020, and 1.02 (95% CI, 0.96-1.07) in January and February 2021 (P < .001 for interaction). The adjusted association of the Gini coefficient with COVID-19 cases also reached a peak in July and August 2020 (relative risk, 1.28 [95% CI, 1.22-1.33]). Conclusions and Relevance: This study suggests that income inequality within US counties was associated with more cases and deaths due to COVID-19 in the summer months of 2020. The COVID-19 pandemic has highlighted the vast disparities that exist in health outcomes owing to income inequality in the US. Targeted interventions should be focused on areas of income inequality to both flatten the curve and lessen the burden of inequality.

Beyond perceptual narrowing: Monolingual and bilingual infants discriminate Hindi contrasts when learning words in the second year of life.

A significant body of literature has demonstrated that infants demonstrate a decline in sensitivity to nonnative sound contrasts by their first birthday, a transition often thought to be adaptive for later word learning. The present study investigated infants' sensitivity to these contrasts in a habituation-based discrimination and word learning task (total N = 168, 78 males and 90 females). All infants were native to Singapore and were of Chinese origin. Family socioeconomic status (SES) was measured by parental education. The mean number of years of parental education was 4.02 years after high school. Using a habituation-based discrimination paradigm, monolingual, and bilingual infants' sensitivity to the Hindi dental/retroflex voiceless stop was investigated at 14 months (Experiment 1). Neither group discriminated the contrast. Using the Switch paradigm, we assessed sensitivity to the same contrast in a word learning task. Monolingual and bilingual infants were tested at 14- and 19 months (Experiment 2a) and subsequently, an older group of bilingual infants was tested at 24 months (Experiment 2b). Results demonstrated an overall sensitivity to the Hindi contrast in Experiment 2a. Bilingual infants tested in Experiment 2b were not sensitive to the Hindi contrast. Findings are discussed with reference to discontinuities in the growth of a phonological lexicon as well as possible mechanisms elicit nonnative sensitivity in word learning. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Sensitivity to race in language comprehension in monolingual and bilingual infants.

Past studies suggest that monolingual and bilingual infants respond differently to race information in face discrimination and social learning tasks. In particular, bilingual infants have been shown to respond more similarly to own- and other-race individuals, in contrast to monolingual infants, who respond preferentially to own-race individuals. In the current study, we investigated monolingual and bilingual sensitivity to speaker race in spoken word recognition. Two-year-old infants were presented with spoken words in association with visual targets. Words were presented in association with own- or other-race actors and were either correctly pronounced or mispronounced. Measuring speech-responsive eye movements to visual targets, we analyzed fixation to visual targets for correct and mispronounced words in relation to speaker race for each group. When presented with own-race speakers, both monolingual and bilingual infants associated correctly pronounced labels, but not mispronounced labels, with visual targets. When presented with other-race speakers, bilingual infants responded similarly. In contrast, monolingual infants did not fixate visual targets regardless of whether words were correctly pronounced or mispronounced by an other-race speaker. Results are discussed in terms of the sensitivities of bilingual and monolingual infants to novelty, learned associations between race and language, and prior social experiences.

Brachial Flow-mediated Dilation and Risk of Dementia: The Cardiovascular Health Study.

INTRODUCTION: Brachial flow-mediated dilation (FMD) is a physiologic measure of endothelial function. We determined the prospective association of brachial FMD with incident dementia among older adults. METHODS: We included 2777 Cardiovascular Health Study participants who underwent brachial FMD measurement. Incident dementia was ascertained by medication use, International Classification of Diseases-9 codes, requirement for a proxy, and death certificates and calibrated to gold-standard assessments performed in a subset of the cohort. RESULTS: Mean participant age at time of brachial FMD measurement was 77.9 years. We identified 1650 incident dementia cases (median follow-up=10.5 y). After adjusting for age, race, sex, education, clinic site, and baseline arterial diameter, risk of dementia for participants in the highest quartile of percent brachial FMD did not differ from those in lowest quartile (hazard ratio=0.89, 95% confidence interval: 0.77, 1.03). CONCLUSIONS: Brachial FMD, measured late in life, is not associated with an increased risk of incident dementia.

Development and application of a survey instrument to measure collaboration among health care and social services organizations.

OBJECTIVE: To measure strategies of interorganizational collaboration among health care and social service organizations that serve older adults. STUDY SETTING: Twenty Hospital Service Areas (HSAs) in the United States. STUDY DESIGN: We developed and validated a novel scale to characterize interorganizational collaboration, and then tested its application by assessing whether the scale differentiated between HSAs with high vs low performance on potentially avoidable health care use and spending for Medicare beneficiaries. DATA COLLECTION: Health care and social service organizations (N = 173 total) in each HSA completed a 12-item collaboration scale, three questions about collaboration behaviors, and a detailed survey documenting collaborative network ties. PRINCIPAL FINDINGS: We identified two distinguishable subscales of interorganizational collaboration: (a) Aligning Strategy and (b) Coordinating Current Work. Each subscale demonstrated convergent validity with the organization's position in the collaborative network, and with collaboration behaviors. The full scale and Coordinating Current Work subscale did not differentiate high- vs low-performing HSAs, but the Aligning Strategy subscale was significantly higher in high-performing HSAs than in low-performing HSAs (P = .01). CONCLUSIONS: Cross-sector collaboration-and particularly Aligning Strategy-is associated with health care use and spending for older adults. This new survey measure could be used to track the impact of interventions to foster interorganizational collaboration.

Collaboration in Health Care and Social Service Networks for Older Adults: Association With Health Care Utilization Measures.

BACKGROUND: Services targeting social determinants of health-such as income support, housing, and nutrition-have been shown to improve health outcomes and reduce health care costs for older adults. Nevertheless, evidence on the properties of effective collaborative networks across health care and social services sectors is limited. OBJECTIVES: The main objectives of this study were to identify features of collaborative networks of health care and social services organizations associated with avoidable health care use and spending for older adults. RESEARCH DESIGN: Through a 2017 survey, we collected data on collaborative ties among health care and social service organizations in 20 US communities with either high or low performance on avoidable health care use and spending for Medicare beneficiaries. Six types of ties were measured: any collaboration, referrals, sharing information, cosponsoring projects, financial contracts, and joint needs assessment. We examined how characteristics of collaborative networks were associated with performance. RESULTS: High-performing networks were distinguished from low-performing networks by 2 features: (1) health care organizations occupied positions of significantly greater centrality (P<0.01), and (2) subnetworks of cosponsorship ties were more cohesive, as measured by centralization (P=0.05) and density (P=0.06). Across all networks, Area Agencies on Aging were more centrally positioned than any other type of organization (P<0.05). CONCLUSIONS: Cross-sector engagement by health care organizations, particularly development of deeper types of collaborative ties such as cosponsorship, may reduce preventable health care use and spending. Efforts to foster effective partnerships could leverage the Area Agencies on Aging, which are already positioned as network brokers.

District-level health management and health system performance.

Strengthening district-level management may be an important lever for improving key public health outcomes in low-income settings; however, previous studies have not established the statistical associations between better management and primary healthcare system performance in such settings. To explore this gap, we conducted a cross-sectional study of 36 rural districts and 226 health centers in Ethiopia, a country which has made ambitious investment in expanding access to primary care over the last decade. We employed quantitative measure of management capacity at both the district health office and health center levels and used multiple regression models, accounting for clustering of health centers within districts, to estimate the statistical association between management capacity and a key performance indicator (KPI) summary score based on antenatal care coverage, contraception use, skilled birth attendance, infant immunization, and availability of essential medications. In districts with above median district management capacity, health center management capacity was strongly associated (p < 0.05) with KPI performance. In districts with below median management capacity, health center management capacity was not associated with KPI performance. Having more staff at the district health office was also associated with better KPI performance (p < 0.05) but only in districts with above median management capacity. The results suggest that district-level management may provide an opportunity for improving health system performance in low-income country settings.

Links between social environment and health care utilization and costs.

The social environment influences health outcomes for older adults and could be an important target for interventions to reduce costly medical care. We sought to understand which elements of the social environment distinguish communities that achieve lower health care utilization and costs from communities that experience higher health care utilization and costs for older adults with complex needs. We used a sequential explanatory mixed methods approach. We classified community performance based on three outcomes: rate of hospitalizations for ambulatory care sensitive conditions, all-cause risk-standardized hospital readmission rates, and Medicare spending per beneficiary. We conducted in-depth interviews with key informants (N = 245) from organizations providing health or social services. Higher performing communities were distinguished by several aspects of social environment, and these features were lacking in lower performing communities: 1) strong informal support networks; 2) partnerships between faith-based organizations and health care and social service organizations; and 3) grassroots organizing and advocacy efforts. Higher performing communities share similar social environmental features that complement the work of health care and social service organizations. Many of the supportive features and programs identified in the higher performing communities were developed locally and with limited governmental funding, providing opportunities for improvement.

Patterns of Collaboration among Health Care and Social Services Providers in Communities with Lower Health Care Utilization and Costs.

OBJECTIVE: To understand how health care providers and social services providers coordinate their work in communities that achieve relatively low health care utilization and costs for older adults. STUDY SETTING: Sixteen Hospital Service Areas (HSAs) in the United States. STUDY DESIGN: We conducted a qualitative study of HSAs with performance in the top or bottom quartiles nationally across three key outcomes: ambulatory care sensitive hospitalizations, all-cause risk-standardized readmission rates, and average reimbursements per Medicare beneficiary. We selected 10 higher performing HSAs and six lower performing HSAs for inclusion in the study. DATA COLLECTION: To understand patterns of collaboration in each community, we conducted site visits and in-depth interviews with a total of 245 representatives of health care organizations, social service agencies, and local government bodies. PRINCIPAL FINDINGS: Organizations in higher performing communities regularly worked together to identify challenges faced by older adults in their areas and responded through collective action-in some cases, through relatively unstructured coalitions, and in other cases, through more hierarchical configurations. Further, hospitals in higher performing communities routinely matched patients with needed social services. CONCLUSIONS: The collaborative approaches used by higher performing communities, if spread, may be able to improve outcomes elsewhere.

Leveraging the Social Determinants of Health: What Works?

We summarized the recently published, peer-reviewed literature that examined the impact of investments in social services or investments in integrated models of health care and social services on health outcomes and health care spending. Of 39 articles that met criteria for inclusion in the review, 32 (82%) reported some significant positive effects on either health outcomes (N = 20), health care costs (N = 5), or both (N = 7). Of the remaining 7 (18%) studies, 3 had non-significant results, 2 had mixed results, and 2 had negative results in which the interventions were associated with poorer health outcomes. Our analysis of the literature indicates that several interventions in the areas of housing, income support, nutrition support, and care coordination and community outreach have had positive impact in terms of health improvements or health care spending reductions. These interventions may be of interest to health care policymakers and practitioners seeking to leverage social services to improve health or reduce costs. Further testing of models that achieve better outcomes at less cost is needed.

Epidemiology of Drug Use and HIV-Related Risk Behaviors among People Who Inject Drugs in Mwanza, Tanzania.

Heroin trafficking and consumption has increased steadily over the past decade in Tanzania, but limited information regarding HIV and drug use exists for the city of Mwanza. Our study investigates the epidemiology of drug use, and HIV risk behaviors among drug users in the northwestern city of Mwanza. Using a combination of targeted sampling and participant referral, we recruited 480 participants in Mwanza between June and August 2014. The sample was 92% male. Seventy-nine (16.4%) participants reported injecting heroin, while 434 (90.4%) reported smoking heroin. Unstable housing and cohabitation status were the only socioeconomic characteristics significantly associated with heroin injection. More than half of heroin injectors left syringes in common locations, and half reported sharing needles and syringes. Other risk behaviors such as lack of condom use during sex, and the use of illicit drugs during sex was widely reported as well. Among the study sample, there was poor awareness of health risks posed by needle/syringe sharing and drug use. Our results show that heroin use and HIV risk related behaviors are pressing problems that should not be ignored in Mwanza. Harm reduction programs are urgently needed in this population.